Incorporation of the electrodes for defibrillation into the patient-facing components of automated cardiopulmonary resuscitation systems

ABSTRACT

An automated resuscitation system is provided, which can improve the outcome of patients suffering ventricular fibrillation or the ventricular tachycardia variants of cardiac arrest. This outcome can be achieved by a device that integrates automatic mechanical or pneumatic capability with electrical countershock capability such that the probability of defibrillation or cardioversion with return of spontaneous circulation is increased.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.No. 62/699,647, filed Jul. 17, 2018, entitled INCORPORATION OF THEELECTRODES FOR DEFIBRILLATION INTO THE PATIENT-FACING COMPONENTS OFAUTOMATED CARDIOPULMONARY RESUSCITATION SYSTEMS, the entire disclosureof which is herein incorporated by reference.

FIELD OF THE INVENTION

The invention disclosed here relates in general to the field ofcardiopulmonary resuscitation (CPR), and more particularly, to devicesand methods for improving the clinical outcome of patients sufferingcardiac arrest.

BACKGROUND OF THE INVENTION

The sudden loss of myocardial pump function, so-called cardiac arrest,is one of the leading causes of sudden death.

Since its first modern description, external chest compression basedcardiopulmonary resuscitation (CPR) as a therapy for cardiac arrest hasbeen extensively studied, and numerous refinements have been proposed.Despite this significant effort, a large majority of patients sufferingsudden death will not be successfully resuscitated to discharge from thehospital capable of independent function. This is even true for patientswhose cardiac arrest occurs within the hospital and who receiveimmediate therapy. Improving the efficacy of resuscitative treatment isone of the great unmet needs in modern medicine.

Cardiopulmonary resuscitation (CPR) may create forward blood flow byapplying force to the patient's thorax either by piston type mechanismsor circumferential constriction mechanisms based on pneumatic or beltconstriction. Application of suction mechanisms may allow activedecompression of the chest. Addition of synchronized abdominalcounterpulsation may additionally enhance the efficacy of CPR. Theefficacy of active decompression CPR may be further enhanced byproviding full or partial obstruction of the airway during portions ofdecompression so as to enhance venous return.

CPR hemodynamics may be further improved by a combination of one or moreof: 1) circumferential constriction, 2) anteroposteriorcompression-decompression of the chest, as taught in U.S. publishedpatent application No. 2016/0361228A1, to Norman A. Paradis, titledMECHANICAL CARDIOPULMONARY RESUSCITATION COMBINING CIRCUMFERENTIALCONSTRICTION AND ANTEROPOSTERIOR COMPRESSION OF THE CHEST, the teachingsof which are incorporated herein by reference, abdominalcounterpulsation and pulsation, abdominal counterpulsation, extremitytourniqueting or pulsation, among others.

Ventricular fibrillation is one of the most common forms of cardiacarrest. It is a chaotic electrical state that precludes coordinateddepolarization of the cardiac ventricles resulting in no cardiac output.It is generally treated with cardiopulmonary resuscitation (CPR) andelectrical defibrillation (U.S. Pat. No. 3,093,136). Ventriculartachycardia is a clinical state in which the hearts ventricles arebeating too rapidly. It may also result in clinical cardiac arrest, andits treatment may be similar to that of ventricular fibrillation.

Medical personnel refer to defibrillation with respect to a fibrillatingheart, and cardioversion or countershock for termination of pulselessventricular tachycardia. For the purposes of this disclosure, the terms“defibrillation” “shock” and “countershock” will be used interchangablywith the understanding that they incorporate termination of eitherventricular fibrillation or tachycardia.

Commonly, electrical countershock is performed by applying electricalpotential—and thus current—across the chest via electrodes connected toa capacitor-based defibrillator. Devices for countershock are well knownand consist fundamentally of an electrically charged capacitor connectedto electrodes on or within the patient and a switch between thecapacitor and the electrodes. (U.S. Pat. No. 3,093,136A). The electrodeson the patient were ferrous metal paddles for many years, but have nowbeen supplanted by adhesive gel electrode pads (U.S. Pat. No.4,539,996).

Improving the Efficacy of Electrical Countershock

The success of electrical countershock is principally associated withimproved current flow across the fibrillating myocardium, which isitself a function of transthoracic resistance when using direct current.Decreasing transthoracic resistance is associated with improved currentflow and techniques which lower transthoracic resistance would improveelectrical countershock success. The equivalent of transthoracicresistance when using alternating current is transthoracic impedance,and measurement of transthoracic impedance with a small AC current maybe used as a surrogate indicator of transthoracic resistance.

Current flow through the chest during electrical countershock may not belinear from one electrode to another, but may be nonlinear as a functionof tissue and organ resistance, capacitance, or impedance. This patternmay be affected by mechanical processes such as chest compression orconstriction. Air is an insulator, so the ventilatory cycle of the lungsmay affect electrical countershock.

Various practitioners have described improved efficacy of defibrillationwhen the electrical counter shock is applied within 300 ms of chestrelease during CPR, as described in U.S. Pat. Nos. 8,478,401, 4,198,963,5,626,618, and 7,186,225, the entire teachings of which are incorporatedherein by reference. Esibov et al. confirmed earlier observations thatvarying the location of the defibrillation pads or paddles placementaffects the efficacy of defibrillation. They noted that the exigenciesof emergency resuscitation may interfere with optimal placement of pads.

The efficacy of electrical countershock may be significantly improved byapplication of multiple transthoracic pathways that are electrified nearsimultaneously or sequentially, as described in U.S. Pat. No. 9,174,061,the entire teachings of which are incorporated herein by reference.

The efficacy of electrical countershock may also be significantlyimproved by applying the countershock only when the myocardium is readyto achieve defibrillation followed by ROSC, as described in U.S. Pat.Nos. 5,571,142, and 5,957,856, the entire teachings of which areincorporated herein by reference. The state of the myocardium may beevaluated in any number of ways. In particular, Fourier transformationof the VF waveform into a power spectrum has provided predictivebiomarkers.

Various practitioners have described a lowered transthoracic resistanceto current flow with the application of force on defibrillationpaddles—called paddle contact pressure. The transition from paddles toadhesive gel pads may actually have negatively affected this parameteras providers did not physically apply contact pressure. Variouspractitioners have demonstrated that applying force to the adhesive gelelectrodes improved transthoracic impedance.

An association has been found between the ventilatory cycle andtransthoracic impedance. They found a higher transthoracic impedancewith inspiration, and a significant decrease in defibrillation successwhen shocks were delivered in inspiration compared to expiration.

In some studies, the performance of defibrillation is improved by usingan anterior-posterior vector. In this scenario, one paddle was placed inthe front of the patient, and another was placed posteriorly between theshoulder blades.

AMSA is a variation in the broad family of techniques to characterizethe state of the myocardium by analysis of the electrocardiogram (ECG)ventricular fibrillation waveform. It was observed decades ago that the“coarseness” of the fibrillatory wave was associated with the likelihoodof defibrillation and ROSC—the coarser the VF waveform, the better. Mostof these techniques are variations of the Fourier transformation, asdescribed in U.S. published patent application No. 2005/0245974, theentire teachings of which are encorporated herein by reference, orarea-under the curve quantification of VF amplitude. For the purposes ofthis disclosure, these will be referred to as ECG-transforms. Persons ofordinary skill will understand that there are multiple specific types orECG-transforms and that any may be used as an indicator or myocardialstatus.

It was observed decades ago that the “coarseness” of the VF wave wasassociated with the likelihood of defibrillation and ROSC—the coarserthe VF waveform, the better. Most of these techniques are variations ofthe Fourier transformation (U.S. Patent No. 2005/0245974) or area-underthe curve quantification of VF amplitude. There are a broad family oftechniques to characterize the state of the myocardium by analysis ofthe ventricular fibrillation waveform. For the purposes of thisdisclosure, these will be referred to as “ECG-transforms.” SuchECG-transforms may be used as goals or targets in resuscitation. Themanner of CPR may be adjusted so as to improve this biomarker. Rescuersmay choose to apply defibrillation only when the biomarker indicatesthat return of spontaneous circulation will occur.

In Summary, the rate of successful transthoracic defibrillation ofventricular fibrillation is increased by:

1) Applying the electrical counter shock during a specific portion ofthe chest compression cycle. (U.S. Pat. Nos. 8,478,401 B2 and 4,198,963and 5,626,618 and 7,186,225).

2) Varying the location of the defibrillation pads or paddles.

3) Using multiple paths across the chest (U.S. Pat. No. 9,174,061). Suchas applying two counter shocks simultaneously at a 90° angle to oneanother.

4) Apply force to the adhesive gel electrodes.

5) Applying the defibrillation shock only when the myocardium is readyto achieve defibrillation followed by ROSC.

5) Applying the shock at an optimal phase or airway pressure of theventilatory cycle.

6) Apply defibrillation in an antero-postero vector and minimizing theantero-postero distance by force.

Improving the Hemodynamics of CPR

The specific mechanisms by which external chest compression achievesforward blood flow remains unclear. Two competing theories have beenproposed: the cardiac pump mechanism and the thoracic pump mechanism. Itis generally believed that anteroposterior compression of the sternumachieves forward blood flow principally through the cardiac pumpmechanism, and that circumferential constriction CPR functions throughthe thoracic pump.

It has been demonstrated that, compared to classical anteroposteriorcompression, circumferential constriction may be associated with higherintrathoracic pressure changes, greater blood flow, and increased ratesof return of spontaneous circulation. Typically, such constriction isgenerally achieved by inflation of a circumferential pneumatic bladder,or semi-circumferentially with a band.

The efficacy of anteroposterior compression may be improved by theaddition of forceful decompression during the upstroke of the piston.Such active decompression requires attachment of the piston device tothe chest. Typically, this is achieved by use of a suction cup device atthe end of the piston.

The improvement in hemodynamics associated with active decompression maybe mechanistically mediated by creation of increased negativeintrathoracic pressure during the decompression phase of CPR, withresulting enhancement of venous return. Additional enhancement ofnegative intrathoracic pressure and venous return may be achieved bybriefly obstructing the airway during the decompression release phase.Typically, this is achieved through utilization of a cracking valvemechanism called an impedance threshold device.

Additional interventions that may improve either circumferentialconstriction or anteroposterior compression of the chest includeadjunctive therapy with pressor drugs, techniques that actively compressor decompress the abdomen, and techniques that synchronize componentswith residual cardiac function, among others. Application of atourniquet to the extremities during CPR has been described as have therhythmic synchronized constriction of the extremities.

Indicators of patient and myocardial status during ventricularfibrillation cardiac arrest include end-tidal CO2 (ET-CO2) and amplitudespectral area (AMSA) among others. These biomarker indicators areassociated with ROSC and defibrillation success respectively. They canbe used in control precision adaptive sequencing for optimization of CPRand the timing of the defibrillatory shocks.

The use of electronic systems to control the parameters of automated CPRsystems has also been described in U.S. Pat. No. 9,566,210, The entireteachings of which are incorporated herein by reference.

In Summary: the efficacy of resuscitation may potentially be improvedby:

-   -   1) Mechanical or pneumatic automated CPR devices, including: A)        chest compression, B) chest decompression, C) chest        constriction, D) abdominal Counterpulsation.    -   2) Methods for improving the efficacy of defibrillation,        including: A) pushing on the electrodes, B) multiple current        paths, C) synchronizing with ventilation, D) synchronizing with        chest compressions.

However, even with these innovations having been described, a largefraction of patients suffering cardiac arrest are not successfullyresuscitated. Principally, this may be because manual CPR is of onlylimited efficacy, and automatic mechanical systems have not had superiorperformance. Further improvements in the efficacy of CPR systems areurgently needed.

SUMMARY OF THE INVENTION

This present disclosure overcomes disadvantages of the prior art byproviding an apparatus and system to improve the outcome of patientssuffering the ventricular fibrillation or the ventricular tachycardiavariants of cardiac arrest. This can be achieved by a device that fullyintegrates automatic mechanical or pneumatic capabilities withelectrical countershock capabilities such that the probability ofdefibrillation or cardioversion with return of spontaneous circulationis increased.

This integrated CPR device contains a defibrillation subsystem that canbe optimized both mechanically, with respect to contact pressure, andelectrically with respect to both timing within the CPR cycles andelectrical current flow.

The present disclosure includes a fully integrated cardiac arrestresuscitation system. The subsystems that interact with the patient toinduce forward blood flow can be optimized and synchronized with thecountershock subsystem to improve the success rate for defibrillationwith return of spontaneous circulation (ROSC). The sequence, forces anddistances of the mechanical, pneumatic, and countershock subsystems canbe computer controlled. The control system may use pre-defined a priorisequences or may optimize all components based on biomarker or subsystemstatus feedback.

In an illustrative embodiment, an automated resuscitation system (ARS)can include at least one means for compression of the chest thatproduces forward blood flow, a countershock defibrillator subsystem, aplurality of countershock electrodes on patient facing portions of theARS, and a control system that can synchronize chest compressions andcountershocks. The ARS can include electrode contact enhancers. Theelectrode contact enhancers can be the means for compression of thechest that produces forward blood flow. The at least one means forcompression of the chest can include a piston. The at least one meansfor compression of the chest can include bladders adapted to encircle apatient. The ARS can include a ventilation subsystem that synchronizeswith the countershock defibrillator subsystem to enhance the efficacy ofdefibrillation. The ARS can include at least one biomarker sensor, andwherein a force of compression applied by the means for compression isdependent on a measurement from the at least one biomarker sensor. Theplurality of countershock electrodes can include at least two pairs ofcountershock electrodes, and wherein defibrillation is achieved bymultiple sequential current paths across the chest. The ARS can includea backboard, wherein at least one of the plurality of countershockelectrodes is on the patient-facing surface of the backboard. At leastone of the plurality of countershock electrodes can be on thepatient-facing surface of the piston.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention description below refers to the accompanying drawings, ofwhich:

FIG. 1 is a schematic diagram of the automated resuscitation system,showing subsystem interactions with a schematic patient and the flow ofsubsystem and biomarker inputs and outputs, according to an illustrativeembodiment;

FIG. 2A is a perspective view of the automated resuscitation system inthe process of being applied to a patient, according to an illustrativeembodiment;

FIG. 2B is an overview of a processing and controlling system for anautomated resuscitation system, according to an illustrative embodiment;

FIG. 3 is a partially cut-away view of the automated resuscitationsystem around a patient's thorax, showing inner workings including oneof the defibrillation pads pre-installed with the circumferentialconstriction subsystem, according to an illustrative embodiment;

FIG. 4 is a partially cut-away view of the automated resuscitationsystem around a patient's thorax of FIG. 3, shown with pneumaticcomponents selectively pushing on the defibrillation pad to improvecontact pressure, according to an illustrative embodiment;

FIG. 5 is a partially cut-away view of an automated resuscitation systemaround a patient's thorax of FIG. 3, shown with a defibrillationelectrode having an intrinsic pressure bladder, according to anillustrative embodiment;

FIG. 6 is a schematic diagram of an exemplary play-the-winner heuristicsequence for adaptively optimizing the configuration of an integratedCPR system, according to an illustrative embodiment;

FIG. 7 is a flow diagram of exemplary primary and secondary sequencesfor adaptively optimizing an integrated CPR system, according to anillustrative embodiment;

FIG. 8 is a flow diagram of an exemplary clinical process demonstratingan integrated sequence of all ARS subsystems so as to enhancedefibrillation, according to an illustrative embodiment;

FIG. 9 is a partially cut-away view of a thoraciccompression-decompression subsystem of the automated resuscitationsystem, according to an illustrative embodiment; and

FIG. 10 is a perspective view of the automated resuscitation systemincluding an extremity subsystem, according to an illustrativeembodiment.

DETAILED DESCRIPTION

The present disclosure includes an automated resuscitation system toimprove the outcome of patients suffering ventricular fibrillation orventricular tachycardia variants of cardiac arrest. This can be achievedby a device that fully integrates automatic mechanical or pneumaticcapabilities with electrical countershock capabilities such that theprobability of defibrillation or cardioversion with return ofspontaneous circulation is increased. For the purposes of thisdisclosure, the terms “defibrillation” “shock” and “countershock” willbe used interchangably with the understanding that they incorporatetermination of either ventricular fibrillation or tachycardia.

This integrated CPR device contains a countershock subsystem that can beoptimized both mechanically, with respect to contact pressure, andelectrically with respect to both timing within the CPR cycles andelectrical current flow. Current flow can be enhanced by minimizingtransthoracic resistance.

FIG. 1 is a schematic diagram of the automated resuscitation system,showing subsystem interactions with a schematic patient and the flow ofsubsystem and biomarker inputs and outputs, according to an illustrativeembodiment. An Automated Resuscitation System (ARS) 100 can include acontroller 104, various meters, and various subsystems. The meters ofthe subsystem can include an end-tidal carbon dioxide (ET-CO₂) meter108, an ECG 109, and/or one or more other meters 117 that can include anaccelerometer, a force transducer, SPO₂ meter (i.e. Near-InfraredSpectroscopy (NIRS) or similar technologies), plethysmograph, and/or anacoustical microphone. The meters of the subsystem can provide sensorydata 112 to the controller 104. Subsystems of the ARS 100 can include aventilation subsystem 103, a circumferential constriction subsystem 102,a sternal compression-decompression subsystem 101, a countershocksubsystem 105, an abdominal counterpulsation subsystem 106, and anextremity subsystem 107. The various subsystems of the ARS can providesubsystem status data 110 to the controller 104.

The controller 104 can input the sensory data 112 and the subsystemstatus data 110, and the controller 104 can control the varioussubsystems based on the input data. The controller 104 can provideinstructions 120 to the various subsystems. The various subsystems ofthe ARS can act on the patient 118, and the various meters of the ARScan collect data from the patient 118. The ventilation subsystem 103 andthe circumferential constriction subsystem 102 can act on the thorax 113of the patient. The sternal compression-decompression subsystem 101 canact on the thorax 113 and the myocardium 114 of the patient. Thecountershock subsystem 105 can act on the myocardium 114 of the patient.The abdominal counterpulsation subsystem 106 can act on the abdomen ofthe patient. The extremity subsystem 107 can act on the extremities 116of the patient.

The subsystems of the device that interact with the patient to induceforward blood flow, including the circumferential constriction subsystem102, the sternal compression-decompression subsystem 101, the abdominalcounterpulsation subsystem 106, and/or the extremity subsystem 107, canbe optimized and synchronized with the countershock subsystem 105 so asthe improve the success rate for defibrillation with ROSC. The sequence,forces and distances of the various mechanical and/or pneumatic bloodflow subsystems 101, 102, 106, and/or 107, and countershock subsystems105 can be controlled by processor 104. The control system may usepre-defined a priori sequences or may optimize all components based onbiomarker or subsystem status feedback, explained more fully below inregard to FIGS. 7 and 8.

The efficacy of defibrillation can be improved when the electricalcountershock is applied within 300 ms of chest release during CPR.Incorporation of countershock capability within the patient-facingsurface of an automated mechanical or pneumatic system can allowcoordination between chest compression and the timing of defibrillation.

FIG. 2A is a perspective view of the automated resuscitation system inthe process of being applied to a patient, according to an illustrativeembodiment. An ARS 100 can have a patient-supporting backboard 203, andthe ARS can include a housing 202 that can be hinged or removablyconnected to the backboard 203. The ARS 100 can have a controllerprocessor 104 that can control and direct various actions, decisions,and subsystems of the ARS, and can input various measurements and datato support actions and decisions of the controller processor 104,explained more fully below. The ARS 100 can have a countershockdefibrillator that can be capable of delivering a countershock to apatient. The countershock defibrillator can be integrated into thehousing 202, and the controller processor 104 can control and direct thedefibrillator. The ARS 100 can have a sternal compression-decompressionsubsystem 101 that can include a piston 204 that can provide activecompression to the patient 118 and can optionally provide activedecompression to the patient 118. The piston 204 can include a suctioncup on the patient-facing end of the piston 204 that provide activedecompression by pulling on the thorax of the patient. The ARS can havea circumferential constriction subsystem 102. Circumferentialconstriction subsystem 102 can include a pneumatic vest, a constrictingband, and/or a series of bladders. Circumferential constrictionsubsystem 102 can include a plurality of bladders that can bepneumatically or hydraulically filled to provide a constricting force tothe patient 118. The bladders can be a series of elongated pneumaticinflatable linear tubes that can be arranged in parallel, explained morefully below. The ARS 100 can include an abdominal counterpulsationsubsystem 106 that can provide a counterpulsating force to the abdomenof the patient.

The ARS 100 can include defibrillation electrodes 201. Thedefibrillation electrodes 201 can be incorporated into variouspatient-facing components of the ARS, including the backboard 203, thecircumferential constriction subsystem 102, the piston 204, and/or otherpatient facing components of the ARS 100. The ARS can include electrodecontact enhancers. In various embodiments, the piston 204 can be anelectrode contact enhancer, and the piston 204 can provide force to pushthe electrode against the patient. Incorporation of the countershockelectrodes 201 into the patient-facing components of a comprehensiveautomated CPR would address the problem of suboptimal patientorientation with respect to the defibrillation electrodes. The placementof the patient within a comprehensive system would be intrinsically morereliable, providing an optimal location and orientation of thedefibrillation electrodes. Multiple defibrillation electrodes 201 can beplaced in various locations within the patient-facing surfaces of theARS 100.

Multiple defibrillation electrodes 201 can be used to create multipletransthoracic pathways through the patient 118. Electric current can bedirected through selected countershock electrodes 201 to create varioustransthoracic pathways through the patient 118. Defibrillation may beimproved by application of multiple transthoracic pathways that areelectrified near simultaneously or sequentially. Incorporation of thedefibrillation electrodes 201 into the patient facing surfaces of theARS 100 allows for multiple defibrillators to be dischargedsimultaneously or sequentially, and allows for the use of one or moretransthoracic pathways between various defibrillation electrodes 201.

The defibrillation pads 201 for multiple pathways can be integrated intothe patient-facing surface of an ARS system 100, and the capability ofproviding simultaneous or sequential multipath defibrillation can alsobe incorporated into the controller as an automated component. In somecases, an anterior-posterior transthoracic pathway may be optimal. Thepotentially optimal anterior-posterior electrode placement and currentpath may be utilized singly, or as part of a multi-shock simultaneous orsequential pattern.

The ARS 100 can have a controller unit with a processor 104 that cancoordinate the biomarker inputs, CPR, and defibrillation functions at aspeed that can be life-saving. The efficacy of defibrillation can besignificantly improved by applying the defibrillation shock only whenthe myocardium is ready to achieve defibrillation followed by ROSC.Incorporation of the countershock and control systems into a fullyautomated CPR system with a controller 104 allows optimized coordinationbetween defibrillation biomarkers and actual counter shock.

FIG. 2B is an overview of a processing and controlling system for anautomated resuscitation system, according to an illustrative embodiment.An ARS can be controlled by a processor 104 that can include a pluralityof modules, data inputs, and control outputs, and a user interface. Theprocessor can be contained within a general purpose, or a dedicated,computing device 260, such as a PC, laptop, tablet or smartphone. Invarious embodiments, the computing device 260 can be built into, orincorporated within, the housing of the ARS. The computing device caninclude a user interface that can be a keyboard 264, mouse 266, touchscreen or similar device, and a display 262 that can include a graphicuser interface screen. In practice, a user can input instructions for aprocedure through the user interface 264 into the processor 104. Theprograms and/or sub-programs can then process the instructions, collectmeasurements, and provide information to the various subsystems of theARS.

The processor unit 104 can include a biomarker data input module 226,along with an adaptor module 222 and a comparator module 224 that can beused by the processor to optimize the performance of the ARS, explainedmore fully below. The processor unit 104 can include a sternumcompression/decompression subsystem control module 232 that can controlthe functions of the sternum compression/decompression subsystem. Theprocessor 104 can include a circumferential constriction subsystemcontrol module 234 that can control the functions of the circumferentialconstriction subsystem. The processor 104 can include a ventilationsubsystem control module 236 that can control the ventilation subsystem236. The processor 104 can include a countershock subsystem controlmodule 238 that can control the countershock subsystem. The processor104 can include an abdominal counterpulsation subsystem control module240 that can control the abdominal counterpulsation subsystem. Theprocessor 104 can include an extremity subsystem control module 242 thatcan control the extremity subsystem.

FIG. 3 is a partially cut-away view of the ARS around a patient'sthorax, showing inner workings including one of the countershockelectrode pads pre-installed within the circumferential constrictionsubsystem, according to an illustrative embodiment. The ARS 100 caninclude the circumferential constriction subsystem 102, and thecircumferential constriction subsystem 102 can include a series ofbladders 304 that can be a series of elongated pneumatic inflatablelinear tubes that can be arranged in parallel around the thorax 113 ofthe patient. A non-distensible belt 302 can hold the bladders 304 inplace around the thorax 113 of the patient. The ARS can includeelectrode contact enhancers. In various embodiments, the electrodecontact enhancers can be pneumatic or hydraulic bladders. A subset ofthe bladders 304 can also be electrode contact enhancing bladders 301.Electrode pressure enhancing bladders 301 can incorporated behind thecountershock electrodes 201. This subset of bladders 301 can apply forceto the electrodes 201 towards the patient to enhance electrode contactpressure.

Development of adhesive gel electrodes has obviated use of force toenhance contact pressure and lower transthoracic resistance. This hascreated a need for devices to enhance contact pressure separate from anintegrated CPR system for patients in cardiac arrest. Incorporation ofelectrodes into the patient facing surface of a circumferentialconstriction system would allow both enhanced contact pressure andventilatory end-exhalation lung volume for optimization of transthoracicresistance and countershock success. Such a device can be used in awakeor sedated patients undergoing cardioversion for atrial fibrillation.

FIG. 4 is a partially cut-away view of the ARS around a patient's thoraxof FIG. 3, shown with pneumatic components selectively pushing on thecountershock electrode pad to improve contact pressure, according to anillustrative embodiment. The electrode pressure enhancing bladders 301can be selectively filled to press an electrode 201 against the patientto enhance electrode contract pressure, as shown in FIG. 4.

FIG. 5 is a partially cut-away view of an automated resuscitation systemaround a patient's thorax of FIG. 3, shown with a countershock electrode201 having an intrinsic pressure bladder, according to an illustrativeembodiment. In various embodiments, the defibrillator electrode 201 canbe affixed to an electrode pressure bladder 501. The electrode pressurebladder 501 and the defibrillator electrode 201 can be affixed to eachother, and/or can be positioned with the electrode pressure bladder 501located behind the countershock electrode 201, so that the electrodepressure bladder 501 can be inflated to provide pressure on theelectrode 201. The pressure on the electrode 201 from the electrodepressure bladder 501 can press the defibrillator electrode against thepatient to enhance electrode contract pressure.

Incorporation of the electrode pads into the patient-facing componentsof an integrated automated CPR system 201 can allow: 1) application offorce to enhance electrode contact pressure, 2) synchronized andoptimized application of force and countershock during the optimalinterval within the chest compression cycle. Furthermore, incorporationof both the ventilatory and the countershock functions into a fullyintegrated automated CPR system would allow the shock to be administeredduring the optimal expiratory phase of ventilation. Incorporation ofelectrodes into the patient facing surface of a circumferentialpneumatic belt can allow both enhanced contact pressure and ventilatoryend-exhalation for optimization of transthoracic resistance andcountershock success. Such a device can be used in awake or sedatedpatients undergoing cardioversion for atrial fibrillation.

FIG. 6 is a schematic diagram of an exemplary play-the-winner heuristicsequence for adaptively optimizing the configuration of an integratedCPR system, according to an illustrative embodiment. The play-the-winnerheuristic process 600 allows the processor to optimize the parametersfor the ARS. At 602, the processor starts with the current CPRparameters, and the processor directs the ARS to operate using thecurrent parameters. At 604, the one or more meters of the ARS measureone or more biomarkers, and the meters provide the data as an input tothe processor. At 606, the adjustor module of the processor adjusts,adds, or changes a parameter for the ARS, explained more fully below,and the processor directs the ARS to operate using the changedparameters. At 608, the one or more meters of the ARS measure the sameone or more biomarkers that were measured at 604, and the measured datais provided as an input to the processor. At 610, the comparator moduleof the processor compares the biomarker data measured at 604 before theadjustment to the biomarker data measured at 608 after the adjustment,and the comparator module determines, based on the measured biomarkerdata, whether the ARS was more effective before the adjustment or afterthe adjustment.

If the biomarker data is not improved after the change, the failedchange is discontinued at 612, and the process returns to the previouscurrent configuration at 602, or proceeds directly to testing a newparameter change at 606. If the biomarker data is improved after thechange, the successful change is retained at 614, and the changedparameter becomes part of the current configuration. When the successfulchange is retained at 614 and it becomes part of the adjustedparameters, the process 600 can return to 602, or the process 600 canreturn to 606 where another new adjustment or change to the parametersis applied. The heuristic process 600 can include repeatedly cyclingthrough the heuristic process, applying various different parameterchanges (described more fully below) and comparing the new biomarkerdata to the previous biomarker data to determine the optimal parameters.

FIG. 7 is a flow diagram of exemplary primary and secondary sequencesfor adaptively optimizing an integrated CPR system, according to anillustrative embodiment. The play the winner system 700 can include aprimary sequence 710 and a secondary sequence 730. In the primarysequence 710, the processor uses a play-the-winner heuristic 600 toinclude or exclude each of the major effector subsystems in turn. Afterthe primary play-the-winner sequence has determined which subsystemswill be used, the secondary play-the-winner sequence 730 optimizes theperformance parameters of those selected subsystems that remain in theconfiguration at the end of the primary sequence.

At 702, CPR can be started with standard sternal compression only, andat standard force-depth parameters. After the initiation of standardsternal compression, the processor can initiate the primary effectorsubsystem optimization sequence 710. Based on biomarker feedback and theplay-the-winner heuristic 600 of FIG. 6, the processor can add andevaluate sternal decompression, circumferential constriction, abdominalcounterpulsation, and extremity augmentation in turn and a subsystemin/out decision can be made by the processor with respect to each. At712, the adjuster module can add sternum decompression to the ARS, andthe comparator module can evaluate whether sternal decompression leadsto improved biomarkers, and then the processor can include or removesternal decompression from the ARS parameters. At 714, the adjustermodule can add circumferential constriction to the ARS, and thecomparator module can evaluate whether circumferential constrictionleads to improved biomarkers, and then the processor can include orremove circumferential constriction from the ARS parameters. Becausethis sequence is initiated with sternal compression at 702, the in/outdecision for sternal compression cannot be initiated until aftercircumferential constriction evaluation 714. In the subset of patientsin whom circumferential constriction is found to be biomarker enhancing,the utility of sternal compression can then be evaluated using theplay-the-winner heuristic 600. In the other subset of patients—thosewhose biomarkers do not improve with circumferential constriction,sternal compression alone can be retained as the sole thoracicsubsystem.

At 716, the adjuster module can add abdominal counterpulsation to theARS, and the comparator module can evaluate whether abdominalcounterpulsation leads to improved biomarkers, and then the processorcan include or remove abdominal counterpulsation from the ARSparameters. At 718, the adjuster module can add extremity constrictionto the ARS, and the comparator module can evaluate whether extremityconstriction leads to improved biomarkers, and then the processor caninclude or remove extremity constriction from the ARS parameters. Invarious embodiments, all or less than all, of the various subsystems maybe included in the ARS and may be tested using the primary play thewinner system 710 and the heuristic 600. In various embodiments, theorder in which the various subsystems are added and tested can bevaried.

At the end of the primary sequence 710, the system moves on to thesecondary sequence 720 and each subsystem can be optimized in turn usingthe heuristic 600 of FIG. 6. If sternal compression is retained afterthe primary optimization sequence 710, it may be optimized at 732 usingheuristic 600 in the secondary sequence 730. The sternal compressionoptimization 732 can include adjusting and optimizing various parametersincluding force, depth, rate/interval down, interval hold, rate/intervalup, among other parameters and characteristics of pistons pushing onobjects. The comparator module can evaluate whether the one or moreadjustments made at 732 by the adjustor module lead to improvedbiomarkers, and then the processor can include or remove the adjustedparameters from the current parameter configuration of the ARS using theheuristic 600.

If sternal decompression is retained after the primary optimizationsequence 710, it may be optimized at 734 using heuristic 600 in thesecondary sequence 730. The sternal decompression optimization 734 caninclude adjusting and optimizing various parameters including forceabove chest, height above chest, rate/interval up, interval hold at top,among other parameters and characteristics of pistons pulling onobjects. The comparator module can evaluate whether the one or moreadjustments made at 734 by the adjustor module lead to improvedbiomarkers, and then the processor can include or remove the adjustedparameters from the current parameter configuration of the ARS using theheuristic 600.

If circumferential thoracic constriction is retained after the primaryoptimization sequence 710, it may be optimized at 736 using heuristic600 in the secondary sequence 730. The circumferential thoracicconstriction optimization 736 can include adjusting and optimizingvarious parameters including pneumatic force, pneumatic rate, passiveversus active deflation, and forceful deflation, among other parametersand characteristics of belts and bladders constricting objects. Thecomparator module can evaluate whether the one or more adjustments madeat 736 by the adjustor module lead to improved biomarkers, and then theprocessor can include or remove the adjusted parameters from the currentparameter configuration of the ARS using the heuristic 600.

If abdominal counterpulsation is retained after the primary optimizationsequence 710, it may be optimized at 738 using heuristic 600 in thesecondary sequence 730. The abdominal counterpulsation optimization 738can include adjusting and optimizing various parameters including force,depth, rate/interval down, interval hold, rate interval up among otherparameters and characteristics of bladders or pistons pushing onobjects. The comparator module can evaluate whether the one or moreadjustments made at 738 by the adjustor module lead to improvedbiomarkers, and then the processor can include or remove the adjustedparameters from the current parameter configuration of the ARS using theheuristic 600.

If extremity constriction is retained after the primary optimizationsequence 710, it may be optimized at 740 using heuristic 600 in thesecondary sequence 730. The extremity constriction optimization 740 caninclude adjusting and optimizing various parameters including continuousversus intermittent constriction, force, and synchronization patternamong other parameters and characteristics of belts and bladdersconstricting objects. The comparator module can evaluate whether the oneor more adjustments made at 740 by the adjustor module lead to improvedbiomarkers, and then the processor can include or remove the adjustedparameters from the current parameter configuration of the ARS using theheuristic 600.

In various embodiments, all or less than all, of the various subsystemsmay be included in the ARS and may be tested using the secondary playthe winner system 730 and the heuristic 600. In various embodiments, theorder in which the various subsystems are added and tested can bevaried. In various embodiments, the processor can fully optimize eachsubsystem before moving on to the next subsystem. In variousembodiments, the processor can gradually optimize various subsystems inparallel. In various embodiments, the secondary play-the-winner systemcan determine that an optimal set of parameters has been reached andthen can discontinue or temporarily discontinue the optimization. Invarious embodiments, the secondary play-the-winner system can continueto perform the optimizations of FIG. 7 using the heuristic of FIG. 6indefinitely.

FIG. 8 is a flow diagram of an exemplary clinical process demonstratingan integrated sequence of all ARS subsystems so as to enhancedefibrillation, according to an illustrative embodiment. At 802, thecontroller can direct the process to begin with the standard sternalcompressions derived from current American heart Association guidelines.In 2017, the guidelines suggested a compression depth of at least 5 cmin 70 kg adults and a rate of 100 compressions per minute. This canresult in a compression-decompression cycle time of 600 milliseconds foreach cycle. At a 50% duty cycle, this is 300 ms compression phase and300 ms decompression phase.

At 700, the controller can initiate the effector subsystem optimizationprocess of FIG. 7 using the heuristic process 600 of FIG. 6, asexplained above in regard to FIGS. 6 and 7. This adaptive optimizationprocess with the mechanical-pneumatic subsystems allows the processor toincorporate substantial optimizations and improvements into the ARSsystem. The processor can begin to optimize the parameters using thebaseline measurement of ET-CO2 levels from ET-CO2 meter and ECG derivedbiomarkers from ECG, along with any other meters included in the system.Then, based on the play-the-winner sequence described in FIGS. 6 and 7,the effector subsystem optimization at 700 can include the primaryplay-the-winner sequence determining the inclusion or exclusion of wholeeffector subsystems based on standard parameters. The secondaryplay-the-winner sequence optimizes those effector subsystems that remainat the end of the primary sequence.

If sternal compression is retained at 700 after the primary optimizationsequence, it may be optimized in the secondary sequence with respect toforce, depth, rate/interval down, interval hold, rate/interval up, amongother parameters and characteristics of pistons pushing on objects.

If sternal decompression is retained at 700 after the primaryoptimization sequence, it may be optimized in the secondary sequencewith respect to force above chest, height above chest, rate/interval up,interval hold at top, among other parameters and characteristics ofpistons pulling on objects. By way of example, active decompression ofthe sternum may achieve an anterior displacement of 10% greater than thestarting anteroposterior diameter. In normal-sized adults, 200-400 N offorce may be required to achieve this displacement.

If circumferential thoracic constriction is retained at 700 after theprimary optimization sequence, it may be optimized in the secondarysequence with respect to pneumatic force, pneumatic rate, passive versusactive deflation, and forceful deflation, among other parameters andcharacteristics of belts and bladders constricting objects. By way ofexample, circumferential pneumatic thoracic constriction may beperformed simultaneous with each sternal compression, and with pneumaticpressures would be between 180 and 250 mm Hg.

If abdominal counterpulsation is retained at 700 after the primaryoptimization sequence, it may be optimized in the secondary sequencewith respect to force, depth, rate/interval down, interval hold, rateinterval up among other parameters and characteristics of bladders orpistons pushing on objects. By way of example, anterior abdominalpneumatic counterpulsation may occur during the 300 ms relaxation phasesof the chest compression-constriction cycle. This may be achieved with apneumatic bladder or series of bladders cyclically inflated to pressures180- and 250-mm Hg. and constrained within a non-dispensable belt 302.

If extremity optimization is retained at 700 after the primaryoptimization sequence, it may be optimized in the secondary sequencewith respect to continuous versus intermittent constriction, force, andsynchronization pattern among other parameters and characteristics ofbelts and bladders constricting objects. By way of example, extremitycounterpulsation may be via pneumatic constriction during the relaxationphase of the thoracic subsystems, and with pneumatic pressures would bebetween 180 and 250 mm Hg.

At 806, CPR optimized with respect to its subsystems at 700 can then beapplied, possibly along with adjunctive therapies, until organmeasurements such as ECG-AMSA indicate that the myocardium is in a stateassociated with likely ROSC.

At 808, the processor can determine when the measurements indicate thatthe oxygen and energetic state of the myocardium had improved to a levelsufficient for defibrillation with ROSC. These data measurements can beinputs to the controller subsystem. When the processor determines thatthe myocardium has improved to a level sufficient for defibrillationwith ROSC, the processor can proceed to 810.

At 810, the countershock subsystem 105 can charge the electrodes.

At 812, the contact pressure subsystem can pneumatically or mechanicallyapply pressure to the electrodes.

At 814, the ventilation subsystem can discontinue ventilation at the endof the expiration.

At 816, the countershock subsystem can apply standard or alternativecountershock (i.e. simultaneous or sequential) at a predetermined timethat can be just after release of chest compression and constriction. Invarious embodiments the countershock subsystem can apply standard oralternative countershock during the 200 ms just after release of chestcompression and constriction. In various embodiments, the countershockscan be single, simultaneous, or sequential, and can be provided throughone or more various transthoracic pathways.

Each subsystem within this illustrative sequence can provide feedbackinputs to the controller.

If countershock did not result in return of spontaneous circulation, thesequence could be repeated or iteratively adapted based on furtherpermutations in play-the-winner heuristic sequences.

FIG. 9 is a partially cut-away view of a thoraciccompression-decompression subsystem and constriction subsystem of theARS, according to an illustrative embodiment. An ARS 100 can havemultiple pairs of countershock electrodes 201, and the electrodes 201,904, 906 can have various hydraulic, pneumatic, or mechanical means forproviding force on the electrode 201 against the patient. As shown inFIG. 9, the first electrodes 201 have pneumatic bladders 301 behind themto provide force on the electrodes 201. In various embodiments, the ARS100 can have one pair of countershock electrodes, or can have more thantwo countershock electrodes, and in various embodiments the ARS 100 canhave four or more countershock electrodes. In various embodiments, theARS 100 can have a pair of electrodes 902 and 904 positioned to applyposterior-anterior countershocks. The ARS can include a pneumatic orhydraulic bladder 906 in the backboard 203, and the bladder 906 canprovide additional force to push upward, enhancing CPR anddefibrillation. The backboard bladder 906 can push upwards on thepatient to enhance CPR outcomes, and/or can be used to provide forcepushing the electrode against the patient to enhance defibrillationoutcome. The upper defibrillator electrode 904 can be positioned on thepiston 204, so that the piston 204 can provide force on the upperdefibrillator electrode 904 against the patient to provide contactpressure and improve the defibrillation outcome.

In some situations, the defibrillation vectors of anterior to posterioror posterior to anterior between defibrillator electrodes 904 and 906can be a superior transthoracic pathway, and the present device canallow for use of this optimal pathway. This current pathway canpotentially be used singly, but can also be incorporated in dual/doublesequential/simultaneous defibrillation. Resuscitation is often performedwith the patient in a supine position, so it can be difficult to placethe posterior countershock electrode. Incorporation of thedefibrillatory functions into a fully integrated automated CPR systemcauses the posterior electrode to be automatically in contact with thepatient when the patient is placed in the ARS 100 system. Incorporationof the defibrillatory functions into a fully integrated automated CPRsystem also allows the countershock to be administered anterior toposterior or vice versa, and alone or in coordination with anothercountershock pathway. The countershocks can be delivered throughmultiple different transthoracic pathways, and shocks along differenttransthoracic pathways can be delivered sequentially or simultaneously.

FIG. 10 is a perspective view of the automated resuscitation systemincluding an extremity subsystem, according to an illustrativeembodiment. An ARS 100 can have a backboard 203 and a housing 202. TheARS 100 can include a sternal compression/decompression system 101 thatcan be a piston. The ARS system can include extremity constrictors 1001.The extremity constrictors 1001 can be bands, bladders, or straps thatcan be wrapped around the patient's limbs, and the limb constrictors1001 can be hydraulically or pneumatically powered, so that thehydraulic or pneumatic force can cause the constrictors to constrictaround the patient's limbs. The constrictors 1001 can act similar to atourniquet, and can squeeze the blood towards the thorax of the patient.In various embodiments, multiple constrictors 1001 can be used inseries, with a first set of constrictors at the ends of the limbs cansqueeze first, followed by a next set of constrictors closer to thethorax that can continue to squeeze blood closer to the thorax.

In various embodiments, the processor controlling the timing ofdefibrillation can apply the electrical countershock during one or morespecific portions of the chest compression or constriction cycle. Invarious embodiments, the processor controlling the timing ofdefibrillation can apply the current for electrical countershock tovarying patterns of electrodes as a function of measured impedance,resistance, capacitance, indicators of tissue perfusion, the amplitudeof the ventricular fibrillation, the median frequency of the ventricularfibrillation, and/or the power spectra of the ventricular fibrillation.In various embodiments, the processor controlling the defibrillation canapply the current for electrical countershock to differing combinationsof electrodes such that multiple paths across the chest can be utilizedsimultaneously or in sequence. In various embodiments, the processorcontrolling the timing of defibrillation can apply the current forelectrical countershock to combinations of electrodes so that twocountershocks at an angle to one another can be applied simultaneously.In various embodiments, the processor controlling the defibrillation canapply the current for electrical countershock to a series of electrodessuch that the pathway of current flow through the chest can start in oneor more vectors and can transition into a different set of vectors. Invarious embodiments, the mechanical, pneumatic, or hydraulic componentscan vary the force or pattern of chest compression or constriction so asto enhance the efficacy of defibrillation. In various embodiments, themechanical, pneumatic, or hydraulic components can vary the force orpattern of chest compression or constrictions so as to apply forceselectively to the electrodes at the time of their defibrillatorydischarge. In various embodiments, the electrodes can be incorporatedinto various surfaces, including the patient facing surfaces of thepiston, the suction cup, the backboard, struts on either side of thepatient's thorax intended for stabilization, pneumatic or hydraulicbladders, pneumatic or hydraulic vests, constricting belts, thebackboard, or a pneumatic or hydraulic bladder between the patient andthe backboard. In various embodiments, the processor can receivemeasurement data from one or more of thoracic resistance, capacitance,impedance, and/or current flow. In various embodiments, the force,location or timing parameters of chest compression or constriction areadjusted so as to optimize one or more of thoracic resistance,capacitance, impedance, or current flow. In various embodiments, thepattern of synchronized ventilation can be adjusted so as to optimizeone or more of thoracic resistance, capacitance, impedance, and/orcurrent flow. In various embodiments, the electrodes can be removableand disposable. In various embodiments, the permanent patient-facingcomponents can be designed for insertion of electrodes that areremovable and disposable. In various embodiments, the sensory signalscan be input into the processor for the purpose of optimization and/orsynchronization of mechanical CPR or electrical defibrillation, and mayoriginate from one or more of: an electrocardiogram, an accelerometer, aforce transducer, ET-CO2, SPO2, an acoustical microphone or themechanical or electrical subsystems. In various embodiments, the ARS caninclude a mechanical or pneumatic component for continuous orintermittent compression of the abdomen. In various embodiments, the ARScan include an esophageal defibrillation electrode. In variousembodiments, the ARS can include a mechanical or pneumatic component forcontinuous or intermittent compression of the abdomen with one or moreelectrodes on its patient-facing surface.

Various embodiments described herein can include installing andintegrating the defibrillation subsystem into a multimodal automatic CPRsystem capable of one or more of thoraciccompression/decompression/constriction, abdominal counterpulsation,ventilation, and limb constriction.

Various embodiments described herein can include a multimodal CPR systemwhose subsystems may include one or more from a list including: sternalcompression and decompression, thoracic circumferential constriction,abdominal pulsation and counterpulsation, extremity tourniquet orcounterpulsation.

Various embodiments described herein can include utilizing themechanical or pneumatic capabilities of a manual or automatic CPR toenhance the efficacy of the defibrillation system.

Various embodiments described herein can include utilizing theventilatory subsystem of an automatic CPR to enhance the efficacy of thedefibrillation system.

Various embodiments described herein can include utilizing the processorand control system of an automatic CPR device to enhance the efficacy ofthe countershock system.

Various embodiments described herein can include utilizing the thoraciccomponents along with the processor of a multimodal automatic CPR systemto selectively optimize the defibrillation electrode contact pressure.

Various embodiments described herein can include utilizing the processorof a multimodal automatic CPR system to optimize the countershock timingwith respect to the chest compression-decompression andconstriction-relation cycles.

Various embodiments described herein can include utilizing theventilation subsystem and processor of a multimodal automatic CPR systemto optimize the lung inflation such that countershock occurs atend-expiration lung volume.

Various embodiments described herein can include utilizing multiplesubsystems of a multimodal automatic CPR system to provide countershockoptimized with respect to contact pressure, CPR cycle and ventilationcycle.

Various embodiments described herein can include incorporating adual/triple/(N) sequential or simultaneous defibrillation capabilityinto a multimodal automatic CPR system.

Various embodiments described herein can include utilizing multiplesubsystems of a multimodal automatic CPR system to providedual/triple/(N) sequential or simultaneous defibrillation optimized withrespect to contact pressure, CPR cycle and ventilation cycle.

Various embodiments described herein can include a precision adaptivesequence for a multimodal automatic CPR system in which the decisioninputs can be ET-CO₂ for hemodynamics or an AMSA-like transformation ofthe fibrillation ECG.

Various embodiments described herein can include a precision adaptivesequence for a multimodal automatic CPR system including aplay-the-winner heuristic in which the current configuration is chosenadaptively based on the biomarkers as the decision input.

Various embodiments described herein include allowing the change frombaseline itself to be used as a biomarker indicative of patient ormyocardial status in cardiac arrest, and that biomarker can be used forrapid decision support by the control subsystem of a multimodalautomatic CPR system.

Within the context of the invention disclosed herein, the termcountershock subsystem has a significantly expanded spectrum ofcapabilities. It can do more than simply charge the electrodes andrelease current from the storage capacitors. It can further interfacewith the processor, providing status data to the controller andreceiving instructions from the controller. It can countershock viamultiple positive-negative defibrillation electrode pairs. Uponreceiving a countershock instruction the controller countershocksubsystem can activate selective pneumatic or mechanical adjuncts,described above, to increase electrode contact pressure. It can thenprovide electrical countershock that may be single, dualsimultaneous/sequential, or N simultaneous/sequential, which can be twoor more simultaneous/sequential countershocks. One of the electrodepairs may include a positive or negative electrode within the esophagus.

The patient-facing components for electrical countershock, such asadhesive gel electrodes, and the associated electronics such as theprocessor may be fully incorporated into the housing of an automatedmechanical/pneumatic CPR system. Alternatively, one or more of thesubsystems may be housed separately from the main device. In the case ofthe countershock subsystem, it may be housed separately and connected tothe main device by electrical cables. A system integrating multiplehemodynamic enhancements with defibrillation enhancements may, at anygiven moment, only be applying a subset of its multiple modalities.

Subsystems that interact with the patient mechanically, pneumatically orkinetically to induce or enhance forward blood flow may be one or moreselected from the group consisting of: thoracic anteroposterocompression; thoracic anteropostero decompression; thoracicconstriction; abdominal counterpulsation and pulsation; abdominal cuadadto cephalad rhythmic compression; a pneumatic inflatable bladder undereither the chest and/or abdomen; tourniqueting the extremities, eithercontinuously, or on an interrupted basis; compressing or decompressingthe extremities, either in a pulsation or counterpulsation pattern,either passively or actively, assisted head-up patient positioning,either the whole backboard or a hinged upper section; and/or esophagealballoon inflation or synchronized pulsation.

Pneumatic systems may apply force to the patient for creation of forwardblood flow by means of a number of mechanisms that may be selected fromthe group consisting of: via a classic piston compression mechanism; viaa suction mechanism piston-type active decompression mechanism; via apneumatically inflatable cuff or bladder; via a pneumatically inflatablecuff or bladder constrained within a non-distensible outer belt; via aseries of pneumatic inflatable linear tubes constrained within anon-distensible outer belt; tourniquet of the extremities; and/orpulsation or counterpulsation of the extremities via pneumaticallyinflatable circumferential cuffs on the arms and legs.

Biomarker inputs that may be used by the system for control of thehemodynamic or defibrillatory subsystems may be one or more selectedfrom the list consisting of: ET-CO₂; ECG; ECG derived secondary ortertiary indicators such as heart rate variability; ECG derived powerspectra related indictors; ECG amplitude derived indicators; currentlocation of hemodynamic components with respect to the patient, i.e.depth of compression; current status of pneumatic components, i.e. veststate of inflation; indicators of tissue status, i.e. near-infraredspectroscopy-like technologies; and/or indicators of ventilatory status,i.e. airway pressure.

A play-the-winner sequence in the control subsystem, such as theplay-the-winner system described in FIG. 6, could be used to optimizethe system and subsystem configuration, as shown and described in FIG.7. In a particular variation, the keep-the-change/reject-the-changedecision could be based on a delta AMSA/ET-CO₂ heuristic. Specifically,the current AMSA/ET-CO₂ measurements can be defined as a baseline. Thenext hemodynamic subsystem or subsystem performance parameter change canbe added into the current system configuration. At a specified timeinterval (i.e. 10, 20, or 30 seconds) after the change, the AMSA/ET-CO₂can again be measured, and the change (delta=current−baseline)calculated. This value can be utilized by the processor to eitherincorporate the most recent change into the current configuration, orreject it and move on to the next change in the precision adaptivesequence. An increase in the AMSA/ET-CO₂ (equal to or above a predefinedthreshold) can result in incorporation of the most recent change intothe current configuration. A decrease (or absence of increase equal toor above the threshold), can result in rejection of the most recentconfiguration change and progression to the next possible hemodynamicenhancement in the precision adaptive sequence.

An automated system that combines and integrates multimodal hemodynamicand defibrillatory capabilities may further incorporate:

-   -   A. Transthoracic countershock can be applied while allowing the        chest compressions of CPR to continue uninterrupted.    -   B. The pattern of mechanical or pneumatic hemodynamic forces can        be varied so as to enhance the efficacy of countershock.    -   C. The gel electrodes (either adhesive or non-adhesive) can be        incorporated into some or all of the patient-facing components        of the automated CPR system.    -   D. For piston-based components, the electrodes can be        incorporated into the patient-facing portion of the piston or        suction cup and the patient-facing portion of the backboard.    -   E. For circumferential constricting components, the electrodes        can be incorporated into the patient-facing surface of the band,        vest, or pneumatic components.    -   F. The pattern of mechanical forces can be adapted to enhance        the efficacy of defibrillation.    -   G. The control system for defibrillation can time the shock to        the optimal phase of CPR just after release of compression.    -   H. The control system for defibrillation can time the shock to        the optimal phase of assisted ventilation at or near        end-expiration.    -   I. The patient-facing mechanical or pneumatic components can        selectively push on the gel electrodes so as to lower        transthoracic resistance, and the control system can time this        application of force to the moment of defibrillation.    -   J. The patient-facing, pre-installed adhesive defibrillation        electrodes can be in a configuration that allows dual, triple,        or N simultaneous or sequential defibrillation optimized with        respect to the CPR and ventilatory cycles.    -   K. The antero-posterior chest compression capability can be        coordinated with the countershock subsystem such that the        antero-posterior distance can be minimized at the time of        defibrillation.    -   L. Select combinations of electrodes such that multiple paths        across the chest can be utilized.    -   M. Select combinations of electrodes such that two counter        shocks at a 90° angle to one another can be applied        simultaneously.    -   N. Altering the selection of electrodes such that the pathway of        current flow through the chest can start in one or more vectors        and transitions into a different set of vectors.

In piston-type integrated CPR systems, the countershock electrodes maybe on various patient-facing surfaces, including: the piston; thesuction cup in active decompression systems; the backboard; and/orstruts on either side of the patient's thorax intended for stabilizationor additional thoracic compression.

In circumferential thoracic constriction-type integrated CPR systems,the countershock electrodes may be on various patient-facing surfacesincluding: one or more of the pneumatic bladders; the pneumatic vest;one or more constricting belts; struts on either side of the patient'sthorax intended for stabilization or additional thoracic compression;the backboard; and/or a pneumatic bladder between the patient and thebackboard.

The electrical control system for the countershock circuitry may measureone or more of: thoracic resistance, capacitance, impedance, or currentflow. It might also receive status updates from one or more of theeffector subsystems. Such a control system could allow: electricalcountershock without interruption in mechanical chest compression orconstriction; electrical countershock during the optimal portion ofmechanical chest compression or constriction; electrical countershockoptimized by the measurement of one or more of thoracic resistance,capacitance, impedance, or current flow; electrical countershock at theoptimal portion of the ventilatory cycle; optimization of the electricalcountershock by applying current through a selected subset of thepatient-facing electrodes; adjustment of the force, location or timingparameters of chest compression or constriction so as to optimize one ormore of thoracic resistance, capacitance, impedance, or current flow;and/or adjustment of the parameters of synchronized ventilation so as tooptimize one or more of thoracic resistance, capacitance, impedance, orcurrent flow.

The countershock electrodes can be adhesive gel electrodes that can be adisposable component that is pre-manufactured so as to be easilyinserted into or removed from the patient-facing mechanical or pneumaticcomponents.

Sensory signals that input into the electrical components and/orcircuitry for the purpose of optimization and or synchronization ofmechanical CPR or electrical defibrillation may originate from one ormore of: the electrocardiogram, an accelerometer, a force transducer,ET-CO₂, SPO₂ (i.e. NIRS), plethysmography, an acoustical microphone, themechanical or electrical subsystems of the device itself.

By way of non-limiting example, an embodiment can include a fullyintegrated mechanical CPR-defibrillation system that can include:

-   -   A. Hemodynamic subsystems capable of applying mechanical or        pneumatic force to the chest, abdomen, or extremities. One or        more hemodynamic subsystems can be chosen from a group        including: a chest compression subsystem, a chest decompression        subsystem, a chest constriction subsystem, and abdominal        compression decompression subsystem, ventilatory subsystem, and        extremity subsystem.    -   B. An electrical countershock subsystem with a countershock        controller module capable of providing shocks in either a        standard or sequential pattern. The countershock subsystem and        its associated electronics may be physically integrated into the        device, or it can be separate, with or without monitor,        connected to the device by a cable. The electrical countershock        electrodes can be physically integrated into the patient-facing        portions of the hemodynamic components, in particular the        thoracic circumferential constricting subsystem, for example, as        shown in FIGS. 2A, 3, 4, and 5.    -   C. Biomarker subsystems capable of measuring patient or organ        status. One or more biomarker or system status input subsystems        chosen from a group including: ECG, ECG derived biomarkers such        as AMSA, ET-CO₂, indicators of tissue oxygenation or energetics        (i.e. NIRS).    -   D. Gel electrode contact pressure subsystem capable of        pneumatically or mechanically applying pressure to the adhesive        gel electrodes.    -   E. A combination countershock electrode and attached pneumatic        bladder. Inflation of the bladder selectively increases        electrode contact pressure.    -   F. A device-status capability within or in connected to the        control subsystem and able to measure the location, direction,        force or pressure for each of the hemodynamic subsystems. One or        more measurements of subsystem status chosen from a group        including: the chest compression subsystem, the chest        decompression subsystem, the chest constriction subsystem, the        abdominal compression-decompression subsystem, the ventilatory        system, and the extremity sub system.    -   G. A control subsystem capable of controlling each hemodynamic        subsystem based on the biomarker feedback and system status        measurements. The control subsystem can execute predefined        precision adaptive sequences.

Various combinations of a control processor, measurement of subsystemstatus, and a play-the-winner heuristic sequence, may be combined.Further, combination of adaptive optimization sequences with amechanical-pneumatic and countershock subsystems can allow for sequencesand configurations that incorporates a substantial number of advantagesdescribed herein.

In such a configuration and sequence, the system can start with:

-   -   A. Standard sternal compressions derived from current American        heart Association guidelines. In 2017, this was a depth of at        least 5 cm in 70 kg adults and a rate of 100 compressions per        minute. This is 600 ms for each compression-decompression cycle.        At a 50% duty cycle, this is 300 ms compression phase and 300 ms        decompression phase.    -   B. Baseline measurement of ET-CO₂ from an ET-CO₂ meter and ECG        derived biomarkers from ECG. Then, based on the described        play-the-winner sequence, potentially add:    -   C. Active decompression of the sternum to an anterior        displacement of 10% greater than the starting anteroposterior        diameter. In normal-sized adults, 200-400 N of force may be        required to achieve this displacement. Then, based on the        described play-the-winner sequence, potentially add:    -   D. Circumferential pneumatic thoracic constriction simultaneous        with each sternal compression. Vest pneumatic pressure would be        between 180 and 250 mm Hg. Then, based on the described        play-the-winner sequence, potentially add:    -   E. Anterior abdominal pneumatic counterpulsation 106 during the        300 ms relaxation phases of the chest compression-constriction        cycle. This may be achieved with a pneumatic bladder or series        of bladders cyclically inflated to pressures 180- and 250-mm Hg.        and constrained within a non-dispensable belt.

When ECG-AMSA indicates that the oxygen and energetic state of themyocardium had improved to a level sufficient for defibrillation withROSC, the following events can occur in a coordinated fashion, as shownan described in FIG. 8: the ventilation subsystem can discontinueventilation at end expiration; the contact pressure subsystem canpneumatically or mechanically apply pressure to the electrodes; and thecountershock subsystem can apply standard or alternative defibrillation(i.e. simultaneous or sequential) during the 200 ms just after releaseof chest compression and constriction.

In various embodiments, the specific subsystems utilized (i.e. chestcompression, chest decompression, chest constriction, abdominalcounterpulsation), and performance parameters of the hemodynamicsubsystems (i.e. force, distance, pressure, intervals) may be optimizedby way of one or more play-the-winner heuristic sequences.

The foregoing has been a detailed description of illustrativeembodiments of the invention. Various modifications and additions can bemade without departing from the spirit and scope of this invention.Features of each of the various embodiments described above may becombined with features of other described embodiments as appropriate inorder to provide a multiplicity of feature combinations in associatednew embodiments. Furthermore, while the foregoing describes a number ofseparate embodiments of the apparatus and method of the presentinvention, what has been described herein is merely illustrative of theapplication of the principles of the present invention. By way ofnon-limiting examples, the ARS may incorporate any type ofdefibrillation or countershock waveform, including biphasic andmonophasic. The ARS may incorporate any type of mechanical or pneumatictechnology as a source of force or pressure within the CPR system. TheARS may incorporate any type of countershock electrode upon or withinthe patient. The ARS may incorporate any pattern of electrodes upon orwithin the patient. The ARS may incorporate any type of control systemfor the subsystems, including but not limited to: electronic circuits,electronic controllers, or computers. The ARS may incorporate any one ofa multiplicity of sensors for adaptive modification of the subsystems.By way of illustration but not limitation, these sensor measurements mayinclude: the electrocardiogram, VF median frequency, VF power spectra,thoracic impedance, thoracic resistance, current flow, ET-CO₂,measurements of perfusion, measurements of organ or patient status.Accordingly, this description is meant to be taken only by way ofexample, and not to otherwise limit the scope of this invention.Additionally, where the term “substantially” or “approximately” isemployed with respect to a given measurement, value or characteristic,it refers to a quantity that is within a normal operating range toachieve desired results, but that includes some variability due toinherent inaccuracy and error within the allowed tolerances (e.g. 1-2%)of the system. Note also, as used herein the terms “process” and/or“processor” should be taken broadly to include a variety of electronichardware and/or software based functions and components. Moreover, adepicted process or processor can be combined with other processesand/or processors or divided into various sub-processes or processors.Such sub-processes and/or sub-processors can be variously combinedaccording to embodiments herein. Likewise, it is expressly contemplatedthat any function, process and/or processor herein can be implementedusing electronic hardware, software consisting of a non-transitorycomputer-readable medium of program instructions, or a combination ofhardware and software. Accordingly, this description is meant to betaken only by way of example, and not to otherwise limit the scope ofthis invention.

What is claimed is:
 1. An automated resuscitation system (ARS)comprising: a plurality of means adapted for applying pressure to achest that produce forward blood flow; a countershock defibrillationsubsystem; a plurality of countershock electrodes, wherein at least oneof the plurality of countershock electrodes are located on electrodecontact pressure enhancers adapted to press countershock electrodesagainst the chest, wherein a first portion of the plurality of meansadapted for applying pressure to the chest that produce forward bloodflow are the electrode contact pressure enhancers; and a control systemadapted to synchronize chest compressions and countershocks, whereinprior to defibrillation, compression is released by a second portion ofthe means adapted for applying pressure to the chest, so as to allowonset of a chest decompression, the second portion of the means adaptedfor applying pressure to the chest being adapted to produce forwardblood flow, and wherein pressure is applied in the first portion of theplurality of means adapted for applying pressure to the chest, the firstportion located over the countershock defibrillation electrodes, so asto enhance electrode contact pressure during defibrillation, wherebypressure is applied by the first portion of the means adapted forapplying pressure to the chest while defibrillation current is appliedto the countershock electrodes, and pressure is released in the secondportion of the means adapted for applying pressure to the chest whiledefibrillation current is applied to the countershock electrodes.
 2. TheARS of claim 1, wherein the plurality of means adapted for applyingpressure to the chest comprises bladders adapted to encircle all or aportion of a patient's chest.
 3. The ARS of claim 1, further comprisinga ventilation subsystem, wherein the control system synchronizes theventilation subsystem and the countershock defibrillation subsystem. 4.The ARS of claim 3, wherein the control system synchronizes the patternsof ventilation and electrical countershock such that electricalcountershock occurs at end-expiration lung volume.
 5. The ARS of claim1, further comprising at least one biomarker sensor providing biomarkerinformation, and wherein the controller uses the biomarker informationin determining a pattern of synchronization of the chest compressionsand countershocks.
 6. The ARS of claim 1, wherein the plurality ofcountershock electrodes further comprises at least two pairs ofcountershock electrodes, and wherein defibrillation is achieved bymultiple current paths across the chest.
 7. The ARS of claim 1, whereinthe countershock electrodes are incorporated into patient facingsurfaces of one or more of components selected from the list consistingof circumferential constricting bladders, constricting series ofbladders, constricting bands, a suction cup, a backboard, or struts oneither side of the patient's thorax.
 8. The ARS of claim 1, wherein thecontrol system is adapted to increase a contact pressure on thecountershock electrodes at a time of countershock.
 9. The ARS of claim 1wherein the at least one means adapted for applying pressure to thechest inflates a circumferential series of bladders, wherein portions ofthe circumferential series of bladders over the countershock electrodesmay be individually inflated.
 10. The ARS of claim 1, wherein thecontrol system is adapted to increase a force or alter a pattern ofpressure on the chest based on one or more biomarker measurementsselected from a group consisting of thoracic electrical resistance, ECG,EN-tidal CO₂, and ventricular fibrillatory frequency distribution. 11.The ARS of claim 1, wherein the control system is adapted to applycountershock current along a first vector, and then transition to applycountershock current along a second vector.
 12. The ARS of claim 1,wherein the means adapted for applying pressure to the chest is adaptedto deliver a first compression-decompression pattern optimized forproducing forward blood flow, and a second compression-decompressionpattern optimized for increasing the efficacy of electricalcountershock.
 13. The ARS of claim 1, wherein the countershockelectrodes are incorporated into the electrode contact pressureenhancers.
 14. The ARS of claim 1 further comprising an esophagealsubsystem comprising one or more of balloons, countershock electrodes,and sensors.
 15. The ARS of claim 1, wherein the first portion of theplurality of means adapted for applying pressure to the chest areconfigured for insertion of electrodes that are removable anddisposable.
 16. An Automated Resuscitation System (ARS) comprising: acircumferential constriction subsystem, the circumferential constrictionsubsystem comprising a plurality of constrictors adapted to performingcircumferential thoracic constriction to produce blood flow, wherein afirst portion of the constrictors further comprise defibrillationelectrodes on a patient-facing surface of the constrictors, so thatactivation of the first portion of the constrictors increases theelectrode contact pressure between the electrode and the patient; aventilation subsystem capable of providing inhalation and exhalation ofthe lungs; a defibrillation subsystem capable of providing electricalcountershock current to the defibrillation electrodes; a controllercapable of synchronizing and activating the subsystems whereby 1) asecond portion of the constrictors begin to release compression at onsetof a relaxation phase, 2) the first portion of the constrictors maintainor increase compression on the defibrillation electrodes after onset ofthe relaxation phase, and 3) the second portion of the constrictorscontinue to release compression, 4) the ventilation subsystem reachesand holds full exhalation, and then 5) the defibrillation subsystemapplies electrical defibrillation current.